
Solution

1… Bxf3 wins a piece since 2. gxf3 clears the g-file and exposes the white king to Qg5+, followed by Qxb5.
Note that the white bishop on b5 is an undefended piece. Undefended pieces are vulnerable to tactics, as this example illustrates.
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1… Bxf3 wins a piece since 2. gxf3 clears the g-file and exposes the white king to Qg5+, followed by Qxb5.
Note that the white bishop on b5 is an undefended piece. Undefended pieces are vulnerable to tactics, as this example illustrates.